Optics Forum

Post thread

Threads

High School Why do rays of light from the Sun appear to be angled?

  • Hobart
  • · Replies 49 ·
2
Replies
49

Undergrad How do lateral and angular magnification combine in a compound microscope?

  • baseballfan_ny
  • · Replies 5 ·
Replies
5

Undergrad What is really happening in collimation of rays?

  • baseballfan_ny
  • · Replies 7 ·
Replies
7

High School How does polarisation in nature work?

  • jackiepollock
  • · Replies 4 ·
Replies
4

Undergrad A ray crossing 2 media of different indices and energy conservation

  • Paulpaulpa
  • · Replies 1 ·
Replies
1

Undergrad What Lens to Put In Front of an Complex Lens to Push Focal Plane Back?

  • cajer
  • · Replies 2 ·
Replies
2

High School LED light and guitar string (strobe light effect)

  • nmsurobert
  • · Replies 2 ·
Replies
2

High School Why we use spherical mirrors instead of parabolic mirrors?

  • jaumzaum
  • · Replies 18 ·
Replies
18

Undergrad What else can you measure with light transmission besides heart rate?

  • btb4198
  • · Replies 15 ·
Replies
15

High School In optics what do Tp and Ts stand for and what are they?

  • btb4198
  • · Replies 3 ·
Replies
3

Graduate Did Planck think the light emitted from black bodies to be quantised?

  • pkc111
  • · Replies 9 ·
Replies
9

Graduate Mirror coating and BSDF measurement costs?

  • jobeva2706
  • · Replies 1 ·
Replies
1

Graduate Could changes in Earth's rotation significantly affect global agriculture?

  • imotta
  • · Replies 3 ·
Replies
3

Undergrad Polar Ice Caps and the Earth's Speed of Rotation

  • iapaulck45
  • · Replies 1 ·
Replies
1

Graduate Fluorescence of a laser vs its pulse duration

  • TheSearch
  • · Replies 1 ·
Replies
1

Graduate Why does light reflect with a 180 degree phase shift at higher refractive index surfaces?

  • ramsd
  • · Replies 2 ·
Replies
2

Graduate Measuring the speed of light in a straight line

  • MikeandSuch
  • · Replies 19 ·
Replies
19

Undergrad Could the Sky Be Green Under Different Atmospheric Conditions?

  • Doctor U
  • · Replies 7 ·
Replies
7

Graduate How to model light from a star?

  • Haorong Wu
  • · Replies 8 ·
Replies
8

Graduate Position of the principal points of a telephoto lens system

  • MissScience33
  • · Replies 3 ·
Replies
3

Graduate Connect: Coupling Light from 2 LEDs into a Single Fiber

  • Octo
  • · Replies 2 ·
Replies
2

Undergrad How to calculate the focal length and focal point of collimator?

  • Barbossa
  • · Replies 3 ·
Replies
3

Graduate Can a continous wave laser be converted to a more powerful pulsed laser?

  • FTM1000
  • · Replies 23 ·
Replies
23

Undergrad Optics question: Looking at mirrors from parallel to the surface

  • Grasshopper
  • · Replies 6 ·
Replies
6

Graduate How to estimate the interaction time of Raman scattering?

  • linqy
  • · Replies 1 ·
Replies
1

Graduate Crosstalk Algorithm - Optical system

  • btb4198
  • · Replies 12 ·
Replies
12

Undergrad Optics Equations - to reduce height

  • btb4198
  • · Replies 5 ·
Replies
5

High School Converting Lux to W/m^2 for Solar Radiation Measurement

  • SilverSparrow
  • · Replies 9 ·
Replies
9

Undergrad Calculating distance between lux meter and light source

  • san-yas
  • · Replies 2 ·
Replies
2

Undergrad Why should a reflected eyeshine be on top of the eyeball?

  • DaveC426913
  • · Replies 13 ·
Replies
13

High School Mirrors spontaneously cracking

  • derje
  • · Replies 8 ·
Replies
8

Undergrad Virtual and real image with concave mirror at 45 degrees

  • nikosb
  • · Replies 4 ·
Replies
4

Graduate RF transmitter in metal enclosure with reflections

  • genekuli
  • · Replies 32 ·
2
Replies
32

Graduate How does light spreading affect optical interferometer delay lines?

  • GhostLoveScore
  • · Replies 2 ·
Replies
2

Undergrad Mirror box with 1 candela of luminous intensity light source

  • genekuli
  • · Replies 72 ·
3
Replies
72

Undergrad Questions about the definition of a metre (A. P. French's book)

  • KedarMhaswade
  • · Replies 17 ·
Replies
17

Graduate Microwave power consumption with and without reflective walls

  • genekuli
  • · Replies 15 ·
Replies
15

Undergrad Why does ice reflect more light than water?

  • kippert
  • · Replies 20 ·
Replies
20

Undergrad Can the energy in two waves cancel out? If so, why?

  • asada
  • · Replies 5 ·
Replies
5

Graduate Critical angle (symmetry of refraction) confusion

  • Glenn G
  • · Replies 5 ·
Replies
5

Undergrad Relation between spectral intensity and spectral energy density

  • IcedCoffee
  • · Replies 2 ·
Replies
2

Undergrad Using constructive interference of audio frequency waves to lower distortion

  • arivel
  • · Replies 3 ·
Replies
3

Graduate ِAngular distribution of a scattered field

  • Ahmed123
  • · Replies 2 ·
Replies
2

High School The Illusion of Anti-Gravity (aka a Superior Mirage)

  • jedishrfu
  • · Replies 32 ·
2
Replies
32

High School Why does a double glazed window reflection appear as a cross?

  • brbrown
  • · Replies 25 ·
Replies
25

High School Does Combined Luminosity of LEDs Add Up?

  • Euan12345
  • · Replies 1 ·
Replies
1

Graduate Rotation of the plane of polarization of light by glucose

  • greg_rack
  • · Replies 4 ·
Replies
4

Graduate ABCD matrix formalism for concave mirror

  • kelly0303
  • · Replies 5 ·
Replies
5

High School Why does red-green light appear yellow when we perceive it?

  • KingGambit
  • · Replies 6 ·
Replies
6

High School Does UV light penetrate cardboard from indirect sunlight?

  • gamer87
  • · Replies 22 ·
Replies
22

Graduate Interference colors on a vinyl record

  • Orthoceras
  • · Replies 26 ·
Replies
26

Graduate Equation for degree of polarization at Brewster's angle

  • kaasisdebaas
  • · Replies 2 ·
Replies
2

Undergrad Achieving the speed of light at the end of a whip

  • idktbh1
  • · Replies 15 ·
Replies
15

Undergrad Integrating velocity in plane polar coordinates with non-fixed unit vectors

  • warhammer
  • · Replies 2 ·
Replies
2

Graduate Lensmaker's equation when the 2 mediums on both sides of the lens are different

  • phantomvommand
  • · Replies 1 ·
Replies
1

Undergrad Question on Optical Systems and Lenses

  • phys_hep_81
  • · Replies 1 ·
Replies
1

High School What is the Length of a Compound Microscope?

  • songoku
  • · Replies 4 ·
Replies
4

Undergrad Wavelength and size of holes or grating

  • merlyn
  • · Replies 9 ·
Replies
9

Undergrad Unleashing Solar Energy: The Potential of Mirrored Circles and Solar Panels

  • entjan
  • · Replies 7 ·
Replies
7

High School The physics explanation of ~bendy~ rays

  • etotheipi
  • · Replies 4 ·
Replies
4

Is this a diffraction pattern or speckle noise?

  • curious2021
  • · Replies 10 ·
Replies
10

Graduate Does twisted light violate Fermat's principle?

  • fxdung
  • · Replies 11 ·
Replies
11

Graduate A way to make the standing-wave patterns in a microwave oven visible

  • jeffinbath
  • · Replies 4 ·
Replies
4

Undergrad The sources of error in a diffraction grating experiment

  • Adams2020
  • · Replies 7 ·
Replies
7

Undergrad Spectrum of laser light absorbed and re-emitted by a white object

  • small physicist
  • · Replies 7 ·
Replies
7

Undergrad Classical explanation for microwave door shielding

  • em3ry
  • · Replies 19 ·
Replies
19

High School Instrument using two concave lenses

  • songoku
  • · Replies 3 ·
Replies
3

Undergrad Does the ruby laser (the first invented laser) have nonlinear behavior?

  • Sciencestd
  • · Replies 5 ·
Replies
5

Undergrad A heavier person vs. a lighter person diving into a pool

  • Haizakokaru
  • · Replies 6 ·
Replies
6

Graduate Can heavy objects be used to modulate light waves with small amplitude?

  • r731
  • · Replies 4 ·
Replies
4

Undergrad What causes this curious light phenomenon? (video inside)

  • Nantes
  • · Replies 11 ·
Replies
11

Undergrad UV mercury lamps: Changing the 185nm vs 253.7nm ratio

  • neanderthalphysics
  • · Replies 10 ·
Replies
10

Undergrad Why does the polarity of a bass guitar recording vary?

  • attaboy_jhb
  • · Replies 10 ·
Replies
10

Undergrad Do counter-phase waves cancel electron displacement in conductors?

  • lambjx
  • · Replies 5 ·
Replies
5

Undergrad Particle analysis of diffraction

  • Byron Forbes
  • · Replies 1 ·
Replies
1

Graduate How does a wave with circular polarization behave?

  • lambjx
  • · Replies 9 ·
Replies
9

Graduate Interference in thin films; confusion regarding geometry

  • rtareen
  • · Replies 4 ·
Replies
4

High School Adding up illuminations in lux

  • zemiacik2
  • · Replies 10 ·
Replies
10

Graduate Suspended particles and the index of refraction

  • PenderJ
  • · Replies 8 ·
Replies
8

Graduate How does the speed of light change when it enters glass?

  • richengle
  • · Replies 12 ·
Replies
12

Undergrad Can Light Travel Faster Than the Speed of Light in Glass?

  • richengle
  • · Replies 18 ·
Replies
18

Graduate Light as wave or particle: the quantum mechanics view

  • ZapperZ
  • · Replies 17 ·
Replies
17

Undergrad Boundary conditions for TM and TE waves

  • LCSphysicist
  • · Replies 3 ·
Replies
3

Undergrad Circuits and the Speed of Light (2)

  • Byron Forbes
  • · Replies 2 ·
Replies
2

Circuits and the Speed of Light

  • Byron Forbes
  • · Replies 2 ·
Replies
2

Graduate Why is reflectance linear in mixed pigments across VIS-NIR wavelengths?

  • XonDoi
  • · Replies 4 ·
Replies
4

Graduate A living thing made of different photonic molecules?

  • newbie2231
  • · Replies 2 ·
Replies
2

Graduate Deriving the Law of Reflection from Huygens Principle

  • rtareen
  • · Replies 5 ·
Replies
5

Undergrad What is it that makes light rebound off a surface?

  • jeebs
  • · Replies 1 ·
Replies
1

Graduate Where do photons originate in a vacuum filament?

  • Byron Forbes
  • · Replies 17 ·
Replies
17

Undergrad Why find the highest order maxima/minima in slit equations?

  • FortranMan
  • · Replies 3 ·
Replies
3

High School Can we see real, inverted and magnified images without a screen?

  • jaumzaum
  • · Replies 4 ·
Replies
4

Graduate How Does Compton Scattering Influence Backscatter Scanner Technology?

  • FrankJ777
  • · Replies 1 ·
Replies
1

Graduate Diffraction of light and conservation of energy.

  • amjad-sh
  • · Replies 3 ·
Replies
3

High School Negative Concave Lens - Creating a Beam Expander

  • tryingtolearn1
  • · Replies 7 ·
Replies
7

High School How do you explain a plane wavefront based on huygens' principle?

  • iVenky
  • · Replies 2 ·
Replies
2

Undergrad Lens selection for close proximity surface photos

  • Danmo
  • · Replies 11 ·
Replies
11

Undergrad How did CRT electron beam width relate to pixel coverage in raster scanning?

  • artis
  • · Replies 32 ·
2
Replies
32

Graduate Adding Zooming Capability to my Far Infrared Spectrum Sensor

  • rubenhak
  • · Replies 12 ·
Replies
12

Undergrad How is the direction of a harmonic wave expressed?

  • WickedSymphony
  • · Replies 6 ·
Replies
6